x86: rename module scx200_32 to scx200

The module scx200 were renamed to scx200_32 by the
merge of the 32 and 64 bit x86 arch trees.

Keep the _32 prefix on the .c file as it is 32 bit
specific and fix the module name in the Makefile.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>